Sioux Falls
South Dakota

Dissolved oxygen

Dissolved oxygen · mg/L at every place the city samples, upstream to downstream. The Big Sioux sites share one chart because they share one water; Skunk Creek gets its own, because the state assigns it different uses and different numbers.

The Big Sioux, last twelve months

05101520NovMarJul5
  • I-90
  • Falls Park
  • Bahnson
  • Timberline

176 samples · 4.08 to 16.87 mg/L

Warmwater semipermanent fish life — above 5.0 mg/L, year-round · ARSD 74:51:01:48

The Big Sioux, 2012 to 2026

051015202520132015201720192021202320255
  • I-90
  • Falls Park
  • Bahnson
  • Timberline

3,253 samples · 0.85 to 24.45 mg/L

Warmwater semipermanent fish life — above 5.0 mg/L, year-round · ARSD 74:51:01:48

Skunk Creek at Marion Road

0510152025201320152017201920212023202554

855 samples · 2.88 to 22.48 mg/L

Warmwater marginal fish life — above 5.0 mg/L, May 1 to Sept 30 · ARSD 74:51:01:49 Warmwater marginal fish life — above 4.0 mg/L, Oct 1 to Apr 30 · ARSD 74:51:01:49

From the city's SWQ Samples table, as of October 12, 2026. 6 published Dissolved oxygen values fall outside what the instrument could have read; they are listed on the site pages and left off these charts. Dashed lines are published thresholds with the rule cited, drawn for the season the rule names. No sample here is scored against them.